Have created an Assignment that requires a submission in Moodle 2.0.3
Logged in as a student and submitted the assignment as a word document.
Submission appeared to save ok, was viewable by student, was downloadable by student etc.
Logged in as Admin and went to 'View Submitted Assessments' via course admin
Recieved an 'Error Reading from database' message.

Debugging info includes:

Debug info: BIGINT UNSIGNED value is out of range in '(`moodle`.`s`.`timemarked` - `moodle`.`s`.`timemodified`)'
SELECT u.id,u.picture,u.firstname,u.lastname,u.imagealt,u.email,
s.id AS submissionid, s.grade, s.submissioncomment,
s.timemodified, s.timemarked,
COALESCE(SIGN(SIGN(s.timemarked) + SIGN(s.timemarked - s.timemodified)), 0) AS status FROM mdl_user u LEFT JOIN mdl_assignment_submissions s ON u.id = s.userid
AND s.assignment = 1 WHERE u.id IN (6) ORDER BY lastname ASC
[array (
)]
Stack trace:
line 391 of \lib\dml\moodle_database.php: dml_read_exception thrown
line 794 of \lib\dml\mysqli_native_moodle_database.php: call to moodle_database->query_end()
line 1303 of \mod\assignment\lib.php: call to mysqli_native_moodle_database->get_records_sql()
line 642 of \mod\assignment\lib.php: call to assignment_base->display_submissions()
line 369 of \mod\assignment\type\upload\assignment.class.php: call to assignment_base->submissions()
line 57 of \mod\assignment\submissions.php: call to assignment_upload->submissions()